Laboratory Analysis of Causative Factors for the Final Incision Size due to Intraocular Lens Injector Insertion

Purpose

In intraocular lens (IOL) implantation, insertion of the IOL injector enlarges the clear corneal incision. A larger incision size (IS) is associated with a higher risk for surgically induced astigmatism and endophthalmitis. The goal of this study was to determine which parameters most influence the final IS.

Design

Experimental study.

Subjects

A total of 126 cadaver porcine eyes were included in this study.

Methods

We analyzed 409 clear corneal incisions made with 126 injectors from 13 injector models. We noted the vertical diameter and the tip angulation for every model. The corneal thickness of each incision location was measured using Scheimpflug tomography. The IS was measured before and after injector insertion and described as preoperative and final ISs, respectively. During surgery, the insertion depth and incision length were documented. A mixed effects model was applied to analyze the influence of the parameters on the final IS.

Main Outcome Measures

Influence on the final IS.

Results

Increases in the vertical diameter of the injector tip, the preoperative IS and the insertion depth, and a reduction of incision length were all significantly associated with increased final IS (P < 0.05). The conditional Pseudo-R2-Measure was 0.92. The preoperative IS had the largest standardized estimated effect on the final IS, followed by the vertical diameter of the injector tip, insertion depth, and lastly, incision length. Neither corneal thickness nor the tip angle of the injector had a significant effect on the final IS (P > 0.05).

Conclusions

The IOL injector's vertical diameter should be as small as possible to ensure a minimal final IS. The injector's insertion depth may be minimized, and the incision length should be long enough to reduce the final IS. Further studies are needed to confirm the findings in human autopsy eyes and in clinical practice.

Financial Disclosures

Proprietary or commercial disclosure may be found after the references in the Footnotes and Disclosures at the end of this article..

Early versus delayed treatment of lateral condylar fracture of the humerus with > 2 mm displacement in children: a retrospective study

BACKGROUND

The purpose of this study was to investigate the clinical and functional outcomes of early versus delayed treatment of pediatric lateral condylar fractures of the humerus with a displacement greater than 2 mm.

METHODS

Sixty-seven children treated surgically at our hospital from March 2016 to September 2021 for lateral condylar fracture of the humerus with displacement > 2 mm were retrospectively analyzed. The children were divided into two groups where early surgery consisted of patients being operated on within 24-h post-injury (n = 36) and delayed surgery consisted of children operated after 24-h post-injury (n = 31). Clinical and functional results were compared between the two groups.

RESULTS

There were no significant differences between the two groups in terms of operation time, blood loss and incidences of perioperative complications. However, mean length of incision was significantly greater (P < 0.0001) in the delayed treatment group (5.68 ± 1.08 cm) compared to the early treatment group (3.89 ± 0.82 cm). No differences were found in functional outcomes, consisting of the Baumann angle of the affected limb, the carrying angle, Mayo Elbow Performance Score, and Flynn's criteria at final follow-up.

CONCLUSIONS

Delay in surgery for more than 24 h after injury does not influence the clinical and functional results for lateral condylar fracture of the humerus with displacement > 2 mm in children. However, delayed open reduction and pinning may increase the incision length possibly due to increased edema.

Implant Insertion Time and Incision Length in Breast Augmentation Surgery with the Keller Funnel: Results from a Comparative Study

BACKGROUND

The Keller funnel is an easy-to-use mechanical device that aids breast implant insertion. This study analyzed implant insertion time and incision length using the Keller funnel versus conventional manual insertion.

METHODS

This was an analysis of two cohorts of adult patients undergoing primary breast augmentation with anatomical implants at a single center. In the 'insertion time cohort' (N = 20), implants were inserted with a Keller funnel on one side and manually on the other; follow-up lasted 4 years. In the 'incision length cohort,' both implants were inserted with a Keller funnel (N = 50) or manually (N = 50), with follow-up lasting 12 months.

RESULTS

In the insertion time cohort, mean total insertion time (from implant sterile-package opening to final positioning in the pocket) was 35 s (range 13-76 s) with the Keller funnel and 25 s (range 13-43 s) using manual insertion (p = 0.07); the mean time needed to push the implant through the incision was 6 s (range 3-10 s) with the Keller funnel and 16 s (range 13-40 s) with manual insertion (p = 0.04). In the incision length cohort, mean incision length was shorter with the Keller funnel versus manual insertion (35.5 ± 2.1 mm vs. 46.2 ± 3.2 mm; p < 0.001). There were no differences in complications based on insertion method.

CONCLUSION

The Keller funnel was associated with decreased incision length and reduced time to push the implant through the incision. This brings potential clinical advantages in minimizing scarring and reducing contamination of the device.

LEVEL OF EVIDENCE III

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